A scroll compressor is a certain type of compressor that is used to compress refrigerant for such applications as refrigeration, air conditioning, industrial cooling and freezer applications, and/or other applications where compressed fluid may be used. Such prior scroll compressors are known, for example, as exemplified in U.S. Pat. Nos. 6,398,530 to Hasemann; 6,814,551, to Kammhoff et al.; 6,960,070 to Kammhoff et al.; and 7,112,046 to Kammhoff et al., all of which are assigned to a Bitzer entity closely related to the present assignee. As the present disclosure pertains to improvements that can be implemented in these or other scroll compressor designs, the entire disclosures of U.S. Pat. Nos. 6,398,530; 7,112,046; 6,814,551; and 6,960,070 are hereby incorporated by reference in their entireties.
As is exemplified by these patents, scroll compressors conventionally include an outer housing having a scroll compressor contained therein. A scroll compressor includes first and second scroll compressor members. A first compressor member is typically arranged stationary and fixed in the outer housing. A second scroll compressor member is moveable relative to the first scroll compressor member in order to compress refrigerant between respective scroll ribs which rise above the respective bases and engage in one another. Conventionally the moveable scroll compressor member is driven about an orbital path about a central axis for the purposes of compressing refrigerant. An appropriate drive unit, typically an electric motor, is provided usually within the same housing to drive the movable scroll member.
As exemplified, for example in U.S. Pat. No. 7,112,046, the tips of the spiraling scroll ribs of the respective scroll compressor bodies may define axially extending, spiral grooves in which are situated spiral tip seals that engage upon the base of the other scroll compressor body (see e.g. FIG. 7 of the '046 patent showing a groove for the tip seal). Such tip seals provide sealing between the scroll tips of one scroll compressor body and the base of the other scroll compressor body so as to generally prevent compressed fluid leakage from an inner compression chamber which has a higher compressed state to an outer chamber defined on the other side of the scroll rib, which contains lower compressed state. The scroll tip seals are highly efficient and provide for very good sealing capabilities and thereby maintain a high compression efficiency. However, there is a potential drawback of such scroll tip sealing designs. Specifically, if a technician improperly installs the scroll compressor or otherwise electrically couples the compressor to be driven in reverse, a vacuum condition is created which causes the opposed scroll compressor bodies to draw against each other under the force of vacuum pressure. The resilient nature of the scroll tip seals is overcome which leaves a relatively thin metal surface material on the scroll tips that can dig into and damage the base of the other scroll body quickly and thereby cause damage.
The present invention is directed towards improvements over the state of the art.